It has been found that the compounds of formula I have a good affinity to the trace amine associated receptors (TAARs), especially for TAAR1.
The compounds may be used for the treatment of depression, anxiety disorders, bipolar disorder, attention deficit hyperactivity disorder (ADHD), stress-related disorders, psychotic disorders such as schizophrenia, neurological diseases such as Parkinson's disease, neurodegenerative disorders such as Alzheimer's disease, epilepsy, migraine, hypertension, substance abuse and metabolic disorders such as eating disorders, diabetes, diabetic complications, obesity, dyslipidemia, disorders of energy consumption and assimilation, disorders and malfunction of body temperature homeostasis, disorders of sleep and circadian rhythm, and cardiovascular disorders.
The classical biogenic amines (serotonin, norepinephrine, epinephrine, dopamine, histamine) play important roles as neurotransmitters in the central and peripheral nervous system. Deutch, A. Y. and Roth, R. H. (1999) Neurotransmitters. In Fundamental Neuroscience (2nd edn) (Zigmond, M. J., Bloom, F. E., Landis, S. C., Roberts, J. L., and Squire, L. R., eds.), pp. 193-234, Academic Press. Their synthesis and storage, as well as their degradation and reuptake after release are tightly regulated. An imbalance in the levels of biogenic amines is known to be responsible for the altered brain function under many pathological conditions. Wong, M. L. and J. Licinio (2001)Nat. Rev. Neurosci., 2, 343-351; Carlsson, A. et al. (2001) Annu. Rev. Pharmacol. Toxicol, 41, 237-260; Tuite, P., and J. Riss (2003) Expert Opin. Invest. Drugs, 12, 1335-1352; Castellanos, F. X. and R. Tannock (2002) Nat. Rev. Neurosci., 3, 617-628.
A second class of endogenous amine compounds, the so-called trace amines (TAs) significantly overlap with the classical biogenic amines regarding structure, metabolism and subcellular localization. The TAs include p-tyramine, β-phenylethylamine, tryptamine and octopamine, and they are present in the mammalian nervous system at generally lower levels than classical biogenic amines. Ursdin, Earl; Sandler, Merton; Editors. Psychopharmacology Series, Vol. 1: Trace Amines and the Brain [Proceedings of a Study Group at the 14th Annual Meeting of the American College of Neuropsychopharmacology, San Juan, Puerto Rico] (1976). Their disregulation has been linked to various psychiatric diseases like schizophrenia and depression and for other conditions like attention deficit hyperactivity disorder, migraine headache, Parkinson's disease, substance abuse and eating disorders Lindemann, L. and M. Hoener (2005) Trends in Phamacol. Sci. 26, 274-281; Branchek, T. A. and T. P. Blackburn (2003) Curr. Opin. Pharmacol., 3, 90-97; Premont, R. T. et al. (2001) Proc. Natl. Acad. Sci. S. A. 98, 9474-9475.
For a long time, TA-specific receptors had only been hypothesized based on anatomically discrete high-affinity TA binding sites in the central nervous system of humans and other mammals. Mousseau, D. D. and R. F. Butterworth (1995) Prog. Brain Res. 106, 285-291; McCormack, J. K. et al. (1986) J. Neurosci. 6, 94-101. Accordingly, the pharmacological effects of TAs were believed to be mediated through the well known machinery of classical biogenic amines, by either triggering their release, inhibiting their reuptake or by “cross reacting” with their receptor systems. Premont, R. T. et al. (2001) Proc. Natl. Acad. Sci. U.S.A. 98, 9474-9475; Dyck, L. F. (1989) Life Sci. 44, 1149-1156; Paker, E. M. and L. X. Cubeddu (1988) J. Pharmacol. Exp. Ther. 245, 199-210. This view changed significantly with the recent identification of several members of a novel family of GPCRs, the trace amine associated receptors (TAARs). Lindemann, L. and M. Hoener (2005) Trends in Pharmacol. Sci, 26, 274-281; Lindemann, L. et al. (2005) Genomics, 85, 372-385. There are 9 TAAR genes in human (including 3 pseudogenes) and 16 genes in mouse (including 1 pseudogene). The TAAR genes do not contain introns (with one exception, TAAR2 contains 1 intron) and are located next to each other on the same chromosomal segment. The phylogenetic relationship of the receptor genes, in agreement with an in-depth GPCR pharmacophore similarity comparison and pharmacological data suggest that these receptors form three distinct subfamilies Lindemann, L. and M. Hoener (2005) Trends in Pharmacol. Sci. 26, 274-281; Lindemann, L. et al. (2005), Genomics, 85, 372-385. TAAR1 is in the first subclass of four genes (TAAR1-4) highly conserved between human and rodents. TAs activate TAAR1 via Gαs. Dysregulation of TAs was shown to contribute to the aetiology of various diseases like depression, psychosis, attention deficit hyperactivity disorder, substance abuse, Parkinson's disease, migraine headache, eating disorders, metabolic disorders and therefore TAAR1 ligands have a high potential for the treatment of these diseases.
The present invention relates to compounds which have a good affinity to the trace amino associated receptors (TAARs), especially for TAAR1.